Commercial dishwashing machines commonly follow a cleaning cycle of prewash, wash and rinse. This is generally true whether the objects being cleaned are flatwear, crockery, pots, pans, etc. Typically, chemicals (detergents) are pumped to the machine for the wash portion of the cleaning cycle.
At the present time, in many installations where commercial dishwashing machines and the like are used, the only cost controls normally analyzed are those attendant with the original purchase price of the equipment and that paid for the chemicals. The frequency of use of a commercial dishwashing machine has not normally been monitored because it has been felt that the costs attendant with such operation are not significant. Thus, in many cases, an entire cleaning cycle will be initiated for a few pieces of flatwear, a half dozen pieces of crockery, or maybe one or two pots and pans and the like.
These dishwashing machines consume water, power and chemicals. More specifically, power, generally in the form of electricity, is required to drive the conveyor which transports the articles to be cleaned; to drive the pumps for moving water from one portion of the machine to another; and to heat the water.
In a typical commercial dishwashing machine, there are at least three zones: a prewash zone, a wash zone and a rinse zone. A primary water system provides hot water at about 180.degree. F. through a valve, such as a solenoid valve, to the nozzle in the rinse zone. This valve may also supply make-up water to the washing and prewash zones. The water drained from the rinse zone is collected in a sump and pumped to the prewash zone through a nozzle and collected in a sump and discharged.
The wash zone typically includes a reservoir of water and an immersion heater to maintain the water at a proper temperature. Water is pumped from this reservoir through a nozzle and is sprayed in the wash zone in combination with chemicals to clean the articles. A stand pipe or other device allows the water to drain off when it reaches a certain level.
Commodities consumed for the various steps in the operation of a dishwashing machine include, but are not limited to, water, chemicals, electric current to drive the motor of the conveyor to pump the water from one zone to the other and to pump the chemicals into the wash zone; energy, gas or electric, is required to generate the primary source of heated water; and a pump is also required for spraying in the wash zone. Also, electric current is required for the immersion
All of these consumed commodities comprise substantially the total cost of the operation of a commercial dishwashing machine. The personnel normally operating such equipment are salaried and do not generally have any incentive to reduce the cost incurred by management in such an operation. It has been found, however, that if a cost reduction system is initiated, that some visual indicia of the continuing costs attendant with such operations is ver instrumental in making the operators of such equipment more aware of the costs involved. However, where the cost of the machine operation is based on intermittant time usage, it is desirable to determine the total cost of operation of such a machine for a single cleaning cycle and for a plurality of cleaning cycles.
The present invention provides a system for measuring the cost of commodities consumed by a commercial dishwashing machine and a method of displaying on a real-time or current basis the actual cost of the commodities being consumed during and after a cleaning cycle.
The present invention in one embodiment is directed to an apparatus and method wherein each distinct commodity consumed is measured to provide an output representative of the cost of each commodity consumed. These outputs are provided on a cost per unit time basis. Further, regardless of the type of input, the outputs are on a common basis, and are totalled to reflect the cost during and at the end of each cleaning cycle.
In the preferred embodiment of the invention, a plurality of metering pumps are responsive to the commodities consumed, i.e., the flow of water and chemicals; and/or the power consumed by the pumps, motors and/or heaters during the entire cleaning cycle. Each of the metering pumps provides a colored liquid output representative of the cost of the commodity consumed which flows to a totalizing device, such as a clear graduated cylinder. Each of the metering devices is calibrated such that the fluid metered is volumetrically consistent with all other outputs.
My invention broadly comprises a dishwashing system having a plurality of zones, in which articles are prewashed in a first zone, washed in a second zone, and rinsed in a third zone. A first nozzle is provided to introduce heated water into the rinse zone. A second nozzle is provided to introduce heated water and chemicals into the wash zone. A first measuring device determines the cost of the heated water introduced into the rinse zone and provides a visual output of said cost. A second measuring device determines the cost of the water and chemicals introduced into the wash zone and provides an output of said costs. The fluid volume of the second output based on cost of commodity consumed is compatible with the output of the first measuring device on the same basis. The outputs are combined and reflect the total cost on a common scale.